i don’t say it is always correct. this is the case when every number is equally possible - not every digit. This is the same as the case, when you can only pick up numbers beetween 0..n-1, where n is the length of a siteswap. and every such zumber is equally probable.

however There are 50 valid siteswaps with period two (I juggling lab’d it), out of a possible 100. (in a case i was talking about there are 4 possible siteswaps(00, 01, 10, 11)and only tow of them are correct)

xy - where x and y are both odd or both even is a siteswap. exactly 50% of two digit strings are siteswaps.

  00 02 04 06 08 - valid siteswap 01 03 05 07 09 invalid  11 13 15 17 19 - valid siteswap 10 12 14 16 18  20 22 24 26 28 - valid siteswap 21 23 25 27 29 invalid  ............—strach